Ngme bivariate model specification

Giving 2 sub_models, build a correlated bivaraite operator based on K = D(theta, eta) $$D(\theta, \rho) = \begin{pmatrix} \cos(\theta) + \rho \sin(\theta) & -\sin(\theta) \sqrt{1+\rho^2} \\ \sin(\theta) - \rho \cos(\theta) & \cos(\theta) \sqrt{1+\rho^2} \end{pmatrix}$$

bv(
  mesh,
  sub_models,
  theta = 0,
  rho = 0,
  group = NULL,
  share_param = FALSE,
  fix_bv_theta = FALSE,
  ...
)

Arguments

mesh

mesh for build the model

sub_models

a list of sub_models (total 2 sub_models)

theta

the rotation parameter (starting point should from -pi/4 to pi/4)

rho

the parameter related to correlation

group

group vector, can be inherited from ngme() function

share_param

TRUE if share the same parameter for 2 sub_models (of same type)

...

ignore

Value

a list of specification of model